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Primer pair designer
Paste the template you want to amplify, set your product-size range, and get ranked primer pairs — each checked for GC content, melting temperature, homopolymer runs and a 3′ GC clamp.
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Best primer pairs
Good to know
A basic designer, honestly labelled
Pairs here satisfy the standard first-pass rules (GC 40–60%, Tm 52–68 °C, matched Tm within a pair). Before ordering, run the winning pair through the in-silico PCR checker on this site and a dimer check — and remember salt and primer concentration shift real Tm values.